A passenger plane and a military helicopter collided mid-air over Washington D.C., crashing into the Potomac River.

The American Airlines flight carried 64 passengers while the helicopter had three military personnel on board. So far 19 bodies have been recovered.

Rescue teams including Coast Guard and national disaster response units, are working, but bad weather is slowing down efforts. Ronald Reagan Airport operations are temporarily halted.

Federal Aviation Administration (FAA) reported that the collision involved Black Hawk military helicopter on a training flight. Authorities are investigating cause of the crash. FBI has also joined the probe.

Families of passengers are gathering at the airport, anxiously waiting for updates. A man told the BBC that he spoke to his wife on the plane just minutes before the crash. She messaged, saying she would land in 20 minutes.

Eyewitnesses said the plane was descending normally but suddenly tilted right. Flames appeared from the rear before it crashed.

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Major commercial plane crashes are rare in the U.S. The last significant crash happened in 2013, when an Asiana Airlines flight crashed during landing in San Francisco, killing three. In 2009, a Colgan Air flight crashed due to a snowstorm, killing 50.

This latest disaster has raised global concerns about air safety.